WASHINGTON – To read about the Duke University freshman turned adult film star is to feel nostalgic for the bygone age of dormitory parietals that barred the opposite sex from visiting the rooms of well-brought-up young ladies.

Of course, such rules are an outmoded relic. Yet their demise reflects a truth about college students. They may no longer be minors but they are more chrysalis than butterfly, not yet fully formed adults. No matter how smart they are, no matter how elite their college, their judgment is impaired – and not just when they’re drinking. They try on identities like so many discarded outfits before a big frat party.

Read Belle Knox, the freshman’s nom de porn, on her decision to pay tuition bills by performing in adult films, and you see the vulnerability underlying the faux-feminist, hear-me-roar bravado about rejecting slut-shaming.

“My experience in porn has been nothing but supportive, exciting, thrilling, and empowering,” Knox – she chose the last name in a weird homage to Amanda Knox, the college student accused of murdering her roommate in Italy – wrote on the website xojane.com. “For me, shooting pornography brings me unimaginable joy. ... It is my artistic outlet: my love, my happiness, my home.”

Methinks the freshman doth protest too much. This is a young woman so insecure that when she first started receiving Facebook friend requests from random male classmates, she was “a bit flattered to be honest (maybe I actually am pretty and nice and not awkward, I thought).” Sally Field, this girl needs to talk to you.

Even more heartbreaking is listening to Knox’s still little-girlish voice describing how she’ll tell her parents. “I don’t want to,” she told the Duke Chronicle last month, in the whiny tone of a child told to go to bed. “I mean, I was thinking I might just tell my mom, ‘Mom, I do modeling where I take my clothes off.’ I might not tell her the whole sex part.”

(Mom knows now; Dad, too. Some newspapers have reported that her father is an Army doctor just home from Afghanistan.)

At other points in her interviews with the Chronicle, Knox reveled in her newfound notoriety. “Do you think I’ll be on ‘Ellen’?” she asked, giggling. Answer: CNN’s “Piers Morgan Live,” last week, wearing a dark suit appropriate for a Goldman Sachs summer internship interview and describing how “thousands of years of patriarchy ... leads us to this point where we so deeply fear sexuality.”

Knox’s argument is that pornography is good for women, a jujitsu move against the patriarchy, because it takes back their sexuality from male-imposed stigma. “A woman who transgresses the norm and takes ownership of her body – because that’s exactly what porn is, no matter how rough the sex is – ostensibly poses a threat to the deeply ingrained gender norms that polarize our society,” Knox wrote.

She mentioned rough sex, which requires an unpleasant discussion of what kind of pornography we’re talking about here and the increasingly violent nature of the Internet-fueled pornography trade.

These are not your father’s Playboys. Knox didn’t just engage in sex for money, and for public consumption; she engaged in debasing acts unfit for description in a family newspaper.

Knox’s pathetic story wouldn’t be worth examining – exploiting? – if it didn’t say something deeper about the hook-up culture run amok and the demise of shame. In an age of sexting and Snapchat, of “Girls Gone Wild” and friends with benefits, perhaps it’s easy to confuse the relative merits of waitressing and sex work.

“To be perfectly honest, I felt more degraded in a minimum-wage, blue-collar, low-paying service job than I ever did doing porn,” Knox said of her high school waitressing job.

But Knox’s experience also calls for discussing the demand side of the pornography transaction. She was outed, after all, by a porn-consuming classmate who recognized his fellow freshman and told his friends.

It would be naive to expect that they, like thousands of teenage boys, don’t spend some computer time on activities other than studying. Fine. Boys will be boys, and girls too, for that matter. What should concern us is the extreme nature of the content they’re viewing, and the way that inevitably seeps into their attitudes toward real-life sex.

One way to look at Belle Knox is to worry about her, and ache for her parents. Another is to worry about what it means for all of us.

Her story doesn’t simply reflect a troubled young woman, it reflects a troubled culture. ■